Chrysler Repair/Misfire

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Question
Hello Ronald.
Strange but the Engine light doesnt come on. But yes there are codes. 300, 301 and 305.

At least I know it's the backside now.
Question, how does the computer know when a cilinder missfires?




Paste of previous conversations:

QUESTION: Hello Ronald.

I'm seeking a professional second opinion here.
So i built my car, changed the front camshaft and my car got better, but still has issues. Heres a few symptons:

The idle is just a biterradic. When driving the car, you can feel the car stumbling a bit. The engine doesnt run smooth. When driving uphill this is a bit worse and you feel it also upon accelerating the car. When reaching 50mph+ the car really stumbles and cant go beyond that speed unless going downhill.

There are no error codes.
The EGR is fine and cleaned.
There are no broken hoses or vacuum leaks

A few things come to mind.
The back sided camshaft could also be worn out.
The harness has to be changed, wires are melted and stick together, although i inspected it and didnt find bare wires touching eachother.
The plugs I have in the car are double platinum, I think they're Bosch though i cant remember. I do remember that they're factory recommended.

Thanks for your reply!
Answer:   Hi Pete,
What compression reading are you now getting on all the cylinders and how do the front bank readings compare to those of the rear bank, which might shed light on your concern about the rear camshaft?
It would be certainly worth the investment to improve the harnesses that show melting has occurred.
Are you certain that you have no codes? That is surprising based upon what you describe. If you are trying via the ignition switch I would suggest that you instead readout the codes with a plugged in code reader.
Thanks for your previous rating and nomination of me. I would appreciated your doing that again for this answer.
Thanks,
Roland

Answer
Hi Pete,
I would believe that if there is a misfire there would be a change in the current being drawn by the primary winding of the spark coil for the misfiring cylinder, and therefore the powertrain controller would detect that because it provides the current to each of the spark coils individually. It might also detect the momentary decrease in rpm which happens with the misfire and can detect which of the cylinders was being provided with spark just before the reduction in rpm occurred. Those would be how I believe the identity for specific cylinder misfiring would be done.
Thanks for rating my previous answer. By the way you can also give me another 'nomination' and it will count (up to 5 nominations in a month for a given "expert" can be made and will be counted).
Roland

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Roland Finston

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Get a Free Fast answer to your repair question about a Chrysler/Dodge/Plymouth car, minivan, SUV, or truck. Problems with electronically controlled engines and transmissions as well as body wiring problems are my specialty. This free troubleshoot advice forum helps you diagnose faults, minimize repair costs or do-it-yourself.

I answer questions seven days a week and respond to you in about 30 minutes. "Maxed Out" means I am answering another question, briefly unavailable, or asleep overnight, so try again later.

I have do-it-yourself experience (50+ years) and a library of 100 1982-2012 Chrysler factory shop manuals and 20 multi-manual Chrysler Corp. CD's.

I was voted "Top Expert" 2010-2015, here at AllExperts, and have answered 20,000+ questions.

Experience

Five decades as a 'do-it-yourselfer' on domestic and imported cars.

Organizations
Yahoo Autos Group called The Chrysler Lebaron Club (co-moderator)

Education/Credentials
Advanced degrees in Physics/bruised knuckles

Awards and Honors
"Top expert" of 2010, 2011, 2012, 2013, 2014 and 2015 here at Allexperts. Quickest "average response time" at Allexperts (currently no. 1).

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